Dr. Anthony Fauci, top U.S. infectious disease expert, is criticizing a group of scientists that supports the concept of herd immunity to combat COVID-19.

Tedros said that too little was known about immunity to COVID-19 to know if herd immunity is even achievable.

A new study has found that relatively few people in Spain have antibodies to the coronavirus, and immunity may not last long.

What is herd immunity and what does it mean for this novel coronavirus? Here's what experts say.